The authors carried out a hospital-based prospective study to evaluate the role of behavioral and clinical risk factors, occurring before and after diagnosis, on the prognosis of 146 patients with newly diagnosed oral cancer using Cox models. High weekly intake of vegetables before and after diagnosis were both associated with lower recurrence rates, longer overall survival and longer oral cancer survival. Diagnostic delay was associated with an increased risk of recurrence and oral cancer mortality. Patients presenting with pharyngeal pain or a mucosal lesion had a longer oral cancer survival than patients presenting with other symptoms. Quitting tobacco and alcohol consumption before and after diagnosis were both associated with a lower recurrence and/or better survival, but the effects were not statistically significant. This study suggests that high consumption of vegetables before and after diagnosis of oral cancer may reduce the risk of recurrence, overall mortality and cancer mortality in oral cancer patients.